The Mass Spectrometry core has been renamed the Mass Spectrometry and Biological Structure (MSBS) Core to reflect increased importance of protein structure analysis. An expert in NMR, Professor Rachel Klevit, has been added to the core as well as an expert in silico protein structure prediction (PSP), Dr Lars Malmstrom. The mass Spectrometry expert remains Professor David Goodlett. As such the core maintains its original goals of providing qualitative and quantitative proteomic analysis, protein post-translational modification analysis, as well as lipid A structure analysis. However, we note that the revised core is devoted to applications of analytical methods as opposed to development of methods in which the original core was engaged. We will use our bioanalytical expertise to conduct the following specific aims on behalf of NWRCE investigators: 1) Determine structures of proteins and protein complexes; 2) Determine structures of small molecules and screen libraries; 3) Characterize Global Protein Regulation; and 4) Consult and Train NWRCE Investigators on Aims 1 - 3. To carry out these aims we will utilize a number of technologies including, but not limited to, the following: 1) High Performance Liquid Chromatography - Electrospray lonization - Tandem Mass Spectrometry. 2) Matrix Assisted Laser Desorption lonization Time-of-Flight Mass Spectrometry. 3) Nuclear Magnetic Resonance Spectroscopy. 4) Computational methods to support interpretation of data.